Synchronizing apparatus for alternators.



No. 717,331. A Patented Dec. 30, |902.

T. D. Boy/LES.

SYNCHRONIZING APPARATUS FUR ALTERNATRS'.

(Application led July 27, 1900.|

:W1-rma ses-E55: INVENTOQ:

. ThomaslD.Boyles,

UNITED STATES PATENT OEEICE.

THOMAS D. BOYLES, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

SYNCHRONIZING APPARATUS FOR ALTERNATORS.

SPECIFICATION forming* parl', 0f Letters Patent No. 717,331, dated December 30, 1902.

' Application leti July 27, 1900. Serial No. 24,989. (No model.) l

To all whom/ t 17m/y concern:

Be it known that I, THOMAS D. BoYLEs, a citizen ofthe United States,residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Synchronizing Apparatus for Alternators, (Case D, No. 1,462 of which the following in a speciication.

lo In systems of electric distribution by alternating currents it is necessary in changing the number of generating units at the station to determine the exact moment of phase identity between a machine about to be cut in and those already connected with the distribution-circuit. It is customary for this purpose to employ as a phase-indicator an incandescent electric lamp which is so arranged that it may be connected in circuit zo with the machine being cut in and with the distributing bus-bars or may be put in inductive relation with these sources, the lamp then indicating by its flashes the proximity of phase of the two sources. Sometimes a z5 Voltmeter is employed as the phase-indicator and is a more accurate means of defining the instant when the phases coincide. Sometimes both phase-indicators are employed, a lamp or lamps being employed on the panel 3o of the switchboard corresponding to each machine and voltmeter being located at some suitable part of the board within View of the operator when throwing in any machine. Thevoltmeterbeingan expensiveinstrument, but a single one is employed for all the machines. To put the voltmeter in the same relation to the lamps of any machine requires considerable wiring unless the circuits be specially designed, and also requires a com- 4c plication in the switch operation to produce the necessary circuit relations to enable them to stand in the same relation to the sources of current being synchronized. My invention involves an organization of this character in which a simple system of wiring permits the voltmeter and lamps to be placed in similar relation to the bus-bars and any machine. Y

In carrying out the invention I provide, in 5 o addition to the synchronizing bus-bars,(which may or may not be the same as the distributing bus-bars,) an auxiliary conductor, with which one terminal of the several synchronizinglamps and the voltmeter connect in parallel, the other terminal of the synchronizing devices connecting with one of the synchronizing bus bars, the latter being adapted to be charged with electric potential by any machine.

My invention also involves switches for 6o throwing into operative relation to any pair of machines the phase-indicating devices.

The several features involved in my invention will be more particularly hereinafter described and will be definitely indicated in the claims appended to the specification.

In the accompanyingdrawings,which illustrate my invention, Figure 1 is a diagram of a system embodying my improvements, and Figs. 2 and 3 are perspective views of plug- 7o switches for coupling the phase-indicating devices into circuit.

1, 1a, and 1b represent a group of alternating-current dynamo-electric machines. 2 and 2a represent theydistributing bus-bars with 75 which said machines may connect in parallel, and 3, 3a, and 3b represent controllingswitches for connecting the respective machines with the bus-bars. On the generator side of each switch is a step-down transformer 8o 4 4@ 4b, the low-potential winding of which is connected to socket-contacts 5 6 5at 6a, dac. These contacts form a part of a group of six contacts, as indicated at 5 6 7 8 9 10, 7 and 8 connecting with a pair of synchronizing bars or conductors 11 11, and 9 and 10 forming the terminals of a branch circuit, including one or more incandescent lamps 12. One of the lamp-terminals is connected by a conductor with a bar 13, this terminal of the sev- 9o eral lamps being in parallel relation with said conductor. Between the conductor 13 and one of the synchronizing-bars, as 11a, is connected a voltmeter 14. For connecting up the machine I provide a six-point plug anda four-point plug, as indicated in Figs. 2 and 3. The dotted lines between the plugs in these figures indicate cross-connections between the plug-contacts to which they lead.

It will be observed that the four-point plug Ioo is cross-connected and that when inserted in contacts 5, 6, 7, and 8, as indicated on the machine at the extreme right of the diagram, it reverses the terminal with the transformer' it connects with respect to the synchronizing bus-bars, thereby putting it in series relation with a transformer connected into circuit by the six-point plug; The latter plug is so arranged that the distance between the contacts 7 and 8 is greater than the distance between the contacts 7 and 9, this being desirable to prevent mistakes on the part of the operator in plugging in a transformer. The diagram Fig. 1 represents the machine 1 as being synchronized. The operator has put the four-point plug in the transformer-circuit of a machine alreadyin the distributioncircuit-as, for example, lb-and the sixpoint plug in circuit with the transformer corresponding to machine 1. It will be seen that the voltmeter 14 and the lamps 12 are in parallel relation to each other and vet are both in series relation to the two machines 1 and 1b. The circuit may betraced as follows: Starting from the lamps 12, we pass to the contact 10, thence across the plug to 5, through the secondary of transformer 4, across the plug from 6 to 8, to the synchronizing bus-bar 11, thence to the four-point plug of machine 1b, through the secondary of transformer 4b and back through the four-point plug to synchronizing-bar 11a, thence to contact 7, and across the plug to contact 9, to the other terminal of the lamp 12. Thus the secondaries of the two transformers 4 and 4b are in series relation with the lamps, and when there is phase identity, as indicated by a steady brilliancy of the lamp, the switch of the machine 3 may be thrown, coupling said machine in parallel relation with the distributing bus-bars 2 and 2*. It will be noted that the voltmeter is in parallel with the lamps, the circuit being from the point 10 by way of conductor 13,voltmeter 14, synchronizing busbar 11a, to contactpoints 7 and 9. It will be observed, moreover, that the voltmeter stands in a similar relation to any machine of the bank which may be connected with the distributing bus-bars. It is therefore evident that a single voltmeter may be used to synchronize and may be employed simultaneously with the lamps, thus affording convenience and accuracy in connecting up the several machines with a simple arrangement of circuits symmetrically arranged and cheap to install.

Having thus described my invention, what I claim as new, and Wish to secure by Letters Patent, is-

1. Means for synchronizing alternating-current dynamo-electric machines, comprising synchronizing bus-bars, a phase-indicator for each machine, means for imposing potentials derived from sources to be synchronized in series relation to the phase-indicator of the machine being synchronized, and a voltmeter in parallel with any phase-indicator connected in circuit.

2. Means forsynchronizing alternating-current dynamo-electric machines comprising a synchronizing-circuit, a phase-indicator for each machine, switches for imposing potentials derived from several machines one of which is to be synchronized in series relation to said circuit, and a voltmeter in said circuit common to all machines in the same relation thereto irrespective of the particular machine being synchronized.

3. Mcansforsynchronizingalternating-current dynamo-electric machines comprising a synchronizing-circuit, transformers for imposing potentials derived from several machines on said circuit, a phase-indicator for each machine, and a voltmeter common to all machines connected across said circuit through a conductorin parallel relation to the several transformers.

4. Means foi-synchronizingalternating-current dynamo-electric machines comprising a synchronizing-circuit,potential-transformers from the several machines in parallel relation to said circuit, a phase-indicator for each machine, a synchronizing-voltmeter common to all machines connected across said circuit through a conductor connected in parallel with the several transformers, and switches for coupling any pair of transformers in the synchronizing-circuit.

5. Means forsynchronizingalternating-current dynamo-electric machines comprising a plurality of transformers corresponding to the several machines, switches for connecting any pair of transformers in circuit, synchronizing-lamps corresponding to the several machines in circuit with said transformers, and a voltmeter in shunt to any lamp when connected.

6. Means forsynchronizing alternating-current dynamo-electric machines comprising transformers corresponding to the several machines, a synchronizing-circuit, switches for connecting two transformers in series in said circuit, an auxiliary synchronizing-conductor, an incandescent lamp in series with the transformer of the machine being synchronized, and a voltmeter in shunt to the lamp through said auxiliary conductor.

In witness whereof I have hereunto set my hand this 24th day of July, 1900.

THOMAS D. BOYLES.

Witnesses:

BENJAMIN B. HULL, LEWIS P. ABELL.

IIO 

